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101.
Incorporation of axonally transported glycoproteins into axolemma during nerve regeneration 总被引:14,自引:4,他引:10 下载免费PDF全文
The insertion of axonally transported fucosyl glycoproteins into the axolemma of regenerating nerve sprouts was examined in rat sciatic motor axons at intervals after nerve crush. [(3)H]Fucose was injected into the lumbar ventral horns and the nerves were removed at intervals between 1 and 14 d after labeling. To follow the fate of the “pulse- labeled” glycoproteins, we examined the nerves by correlative radiometric and EM radioautographic approaches. The results showed, first, that rapidly transported [(3)H]fucosyl glycoproteins were inserted into the axolemma of regenerating sprouts as well as parent axons. At 1 d after delivery, in addition to the substantial mobile fraction of radioactivity still undergoing bidirectional transport within the axon, a fraction of label was already associated with the axolemma. Insertion of labeled glycoproteins into the sprout axolemma appeared to occur all along the length of the regenerating sprouts, not just in sprout terminals. Once inserted, labeled glycoproteins did not undergo extensive redistribution, nor did they appear in sprout regions that formed (as a result of continued outgrowth) after their insertion. The amount of radioactivity in the regenerating nerves decreased with time, in part as a result of removal of transported label by retrograde transport. By 7-14 d after labeling, radioautography showed that almost all the remaining radioactivity was associated with axolemma. The regenerating sprouts retained increased amounts of labeled glycoproteins; 7 or 14 d after labeling, the regenerating sprouts had over twice as much of radioactivity as comparable lengths of control nerves or parent axons. One role of fast axonal transport in nerve regeneration is the contribution to the regenerating sprout of glycoproteins inserted into the axolemma; these membrane elements are added both during longitudinal outgrowth and during lateral growth and maturation of the sprout. 相似文献
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Wei Wei Jinpeng Nong Yong Zhu Guiwen Zhang Ning Wang Suqin Luo Na Chen Guilian Lan Chin-Jung Chuang Yu Huang 《Plasmonics (Norwell, Mass.)》2018,13(2):483-491
Owing to its large surface-to-volume ratio and good biocompatibility, graphene has been identified as a highly promising candidate as the sensing layer for fiber optic sensors. In this paper, a graphene/Au-enhanced plastic clad silica (PCS) fiber optic surface plasmon resonance (SPR) sensor is presented. A sheet of graphene is employed as a sensing layer coated around the Au film on the PCS fiber surface. The PCS fiber is chosen to overcome the shortcomings of the structured microfibers and construct a more stable and reliable device. It is demonstrated that the introduction of graphene can enhance the intensity of the confined electric field surrounding the sensing layer, which results in a stronger light-matter interaction and thereby the improved sensitivity. The sensitivity of graphene-based fiber optic SPR sensor exhibits more than two times larger than that of the conventional gold film SPR fiber optic sensor. Furthermore, the dynamic response analyses reveal that the graphene/Au fiber optic SPR sensor exhibits a fast response (5 s response time) and excellent reusability (3.5% fluctuation) to the protein biomolecules. Such a graphene/Au fiber optic SPR sensor with high sensitivity and fast response shows a great promise for the future biochemical application. 相似文献
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Analysis of key genes and signaling pathways involved in Helicobacter pylori‐associated gastric cancer based on The Cancer Genome Atlas database and RNA sequencing data 下载免费PDF全文
Yi Hu Cong He Jian‐Ping Liu Nian‐Shuang Li Chao Peng Yao‐Bin Yang‐Ou Xiao‐Yu Yang Nong‐Hua Lu Yin Zhu 《Helicobacter》2018,23(5)
Background
Helicobacter pylori (H. pylori) infection is associated with the development of gastric cancer, although the mechanism is unclear. Herein, this study aimed to clarify the key genes and signaling pathways involved in H. pylori pathogenesis based on The Cancer Genome Atlas (TCGA) database and RNA sequencing analysis.Materials and Methods
Forty‐nine gastric cancer samples (16 with H. pylori and 33 without H. pylori) and 35 cancer‐adjacent normal samples from TCGA database were analyzed by bioinformatics. The differentially expressed genes between H. pylori‐positive and H. pylori‐negative patients were verified in 18 gastric cancer (GC) samples (9 with H. pylori and 9 without H. pylori), which were analyzed using RNA sequencing. Survival analysis was carried out to explore associations between the differentially expressed genes and prognosis. Bioinformatics analysis was performed to determine the signaling pathways associated with H. pylori.Results
The baseline level of clinical features from TCGA database and RNA sequencing showed no differences between the H. pylori‐positive and H. pylori‐negative GC groups (P > 0.05). TP53 was shown to be upregulated in the H. pylori‐positive group in both TCGA database and RNA sequencing data, which also showed higher expression in the GC tissues than in adjacent normal tissues (P < 0.05). CCDC151, CHRNB2, GMPR2, HDGFRP2, and VSTM2L were shown to be downregulated in the H. pylori‐positive group by both TCGA database and RNA sequencing, which also showed lower expression in the GC tissues than in adjacent normal tissues (P < 0.05). GC patients with low expression levels of HDGFRP2 had a poor prognosis (P < 0.05). Thirty‐three signaling pathways and 10 biological processes were found to be positively associated with H. pylori infection (P < 0.05, FDR < 0.05).Conclusions
These results indicate that some genes (TP53, CCDC151, CHRNB2, GMPR2, HDGFRP2, VSTM2L) and previously unidentified signaling pathways (eg, the Hippo signaling pathway) might play an important role in H. pylori‐associated GC. 相似文献106.
Gene diagnosis and targeted breeding for blast-resistant Kongyu 131 without changing regional adaptability 总被引:1,自引:0,他引:1
Xiangchun Zhou Gonghao Jiang Longwei Yang Lei Qiu Ping He Chunxiao Nong Yunyue Wang Yuqing He Yongzhong Xing 《遗传学报》2018,45(10):539-547
The fungus Magnaporthe oryzae threatens the rice production of Kongyu 131 (KY131), a leading japonica variety in Northeast China. In this study, two rice lines, KP1 and KP2-Hd1, were obtained by introgressing the blast resistance genes Pi1 and Pi2 into KY131, respectively. However, both lines headed later than KY131. RICE60K SNP array analysis showed that Hd1 closely linked to Pi2 was introgressed into KP2-Hd1, and the linkage drag of Hd1 was broken by recombination. On the other hand, no known flowering genes were introgressed into KP1. Gene diagnosis by resequencing six flowering genes showed that KP1 carried functional Hd16 and Ghd8 alleles. Due to its suppression role in heading under long-day conditions, Ghd8 was chosen as the target for gene editing to disrupt its function. Four sgRNAs targeting different sites within Ghd8 were utilized to induce large-deletion mutations, which were easy to detect via agarose gel electrophoresis. All the ghd8-mutated KP1 lines were resistant to rice blast disease and headed earlier than the control KP1, even than KY131, under natural long-day conditions, which ensures its growth in Northeast China. This study confirmed that a combination of gene diagnosis and targeted gene editing is a highly efficient way to quickly eliminate undesired traits in a breeding line. 相似文献
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Narbonin is a 2S protein from the globulin fraction of narbon bean (Vicia narbonensis L.) cotyledons. Its amino acid composition and the pattern of its regulated accumulation in developing seeds led to the suggestion
that narbonin could be a storage protein. Therefore, it was expected to be present in protein bodies of the storage tissue
cells. Comparison of the cDNA-derived amino acid sequence with a directly determined partial N-terminal sequence revealed
that the primary translation product of narbonin mRNA lacks a transient N-terminal signal peptide (V.H. Nong et al., 1995,
Plant Mol Biol 28: 61–72). Narbonin polypeptides that had been synthesized in a cell-free translation system supplemented
with dog pancreas microsomes were not protected against degradation by posttranslationally added proteases (protease protection
assay). In accordance with the lack of a signal peptide this indicates that the polypeptide was not cotranslationally sequestered
into the microsomes. The protein-body fraction that had been isolated from mature narbon bean cotyledons by a non-aqueous
gradient centrifugation procedure was free of narbonin; this was found in the soluble cell fraction. In electron micrographs,
narbonin could be localized in the cytoplasm using the immuno gold-labelling technique. Previously, it had already been shown
that narbonin is too slowly degraded during narbon bean germination to act as a storage protein. From all these results it
has to be concluded that narbonin is a cytoplasmic protein which does not belong to the storage proteins in the restricted
sense. Other possible functions are discussed.
Received: 18 November 1996 / Accepted: 28 February 1997 相似文献
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